<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>4.1浮动布局</title>
  <style>
    .box{
      width: 606px;
      border: 1px solid red;
      overflow: hidden;
    }
    .item1{
      width: 200px;
      border: 1px solid blue;
      float: left;
    }
    .item2{
      width: 200px;
      border: 1px solid blue;
      float: left;
    }
    .item3{
      width: 200px;
      border: 1px solid blue;
      float: left;
    }
  </style>
</head>
<body>
  <div class="box">
    <div class="item1">item1</div>
    <div class="item2">item2</div>
    <div class="item3">item3</div>
  </div>
  
</body>
</html>